WPF Browser Control - does not run scripts on vista but is fine on XP - why ?

Question

I have an WPF application that hosts a <WebBrowser x:Name="WebBrowser" /> control. After loading I set the control to navigate to a web camera.

this.WebBrowser.Navigate(this.NodeUrl);

This web camera will run some active X controlls.

On an XP machine in the rgular broser IE7 these run fine and I see video.

But the hosted browser in the WPF does nut run the active X.

Any idea how to cure this

<UserControl
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    x:Class="CellStack.UI.Configuration.BrowserDialog">

    <WebBrowser x:Name="WebBrowser" />
</UserControl>

 public BrowserDialog()
        {
            InitializeComponent();

            this.Loaded += new RoutedEventHandler(BrowserDialog_Loaded);
        }

        private void BrowserDialog_Loaded(object sender, RoutedEventArgs e)
        {

            this.WebBrowser.Navigate(this.NodeUrl);
        }